No, without access to WP Admin you would need to rename the folder, but as you have no access to the filesystem this option is not feasible either.
The only remaining option is to connect to the database directly, assuming you know the login details from wp-config.php and the database is configured to allow this. If you do not know the details or the database is configured to not allow this then this option is not available to you. If it is though, then you can delete the activated plugins options in the options table.
Otherwise, you will need to speak with your host to regain access, no technical avenues exist to recover your site unless you can put PHP files up or modify the filesystem in some way.